Who's the best "Evil Twin"?

Personally, I think the best one is Scourge the Hedgehog, because unlike other evil twins who simply try to destroy their originals to be the original, Scourge took time off from trashing Sonic to take over his own universe to distance himself from Sonic the Hedgehog.

are Starfire and Blackfire twins?

no clue

Cassie Nova

o well ill jus say they are so Blackfire and ima agree w. Pix & say Cassie too

Thematically, Peter and Sylar.

"are Starfire and Blackfire twins?"

Casandra Nova.

stryfe!

isn't he a clone?

Hugo Simpson.

"isn't he a clone?"

meh

dont care >:]

Cassandra Nova the evilest twin.